Backend/app/database.py

from sqlalchemy import create_engine
from sqlalchemy.ext.declarative import declarative_base
from sqlalchemy.orm import sessionmaker
from .config import settings

engine = create_engine(
    settings.DATABASE_URL,
    connect_args={"check_same_thread": False},  # required for SQLite
)

SessionLocal = sessionmaker(autocommit=False, autoflush=False, bind=engine)

Base = declarative_base()


def get_db():
    """FastAPI dependency — yields a DB session and closes it after use."""
    db = SessionLocal()
    try:
        yield db
    finally:
        db.close()